Giải thích các bước giải:
\(\begin{array}{*{20}{l}}
{\lim \frac{{2n - 3{n^2}}}{{3n\sqrt n {\rm{ \;}} + 3n + 1}} = \lim \frac{{\frac{2}{n} - 3}}{{\frac{3}{{\sqrt n }} + \frac{3}{n} + \frac{1}{{{n^2}}}}} = {\rm{ \;}} - \infty }\\
{Do:\mathop {\lim }\limits_{n \to + \infty } \frac{3}{{\sqrt n }} + \frac{3}{n} + \frac{1}{{{n^2}}} = {\rm{ \;}} + \infty }\\
{\lim \frac{2}{n} - 3 = {\rm{ \;}} - 3}
\end{array}\)
